System Hang on login screen

Hi all, I just upgraded to 11.2 from 11.1 on a Sony VAIO. It boots fine bit when it reaches the user login screen an attention box pops up and reads "Your saved session type ‘kde’ is not valid anymore. Please select a new one, otherwise the ‘default’ will be used. Then the computer freezes up, no mouse, no keyboard function, just a login screen with an attention box.

At the login screen (Presuming you have auto login disabled!)
Lower left corner where you select the session
You need to switch to kde4. I’m assuming you had kde3 before?

That is what I would do except that as I said, the keyboard and mouse are unresponsive.

Boot to level 3
Here is how.

Pause the boot by moving the down arrow, then move back up to the default boot. But now press backspace, it should delete any text where you can see: vga=0x…

Remove all text and now type just the number:
and hit enter

at the login type your user name and then password

Now do this:
mv /home/username/.kde .kde-old

mv /home/username/.kde4 .kde4-old

( username - Replace with your login user name )

Now switch to su, enter your root password and type

Try logging in